METHOD AND MODULE FOR DETERMINING OF VELOCITY REFERENCE VALUES FOR A VEHICLE CONTROL SYSTEM

• US 20120089312A1
• Filed: 05/31/2010
• Published: 04/12/2012
• Est. Priority Date: 06/10/2009
• Status: Active Grant

• Current Assignee: Scania CV AB (Volkswagen AG)
• Original Assignee: Scania CV AB (Volkswagen AG)
• Inventors: Johansson, Oskar, Hansson, Jörgen, Pettersson, Henrik
• Granted Patent: US 8,620,557 B2
• Time in Patent Office: Days
• US Class Current: 701/93
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 2720/10 Longitudinal speed
• CPC Class Codes: B60W 2720/103 Speed profile
• CPC Class Codes: B60W 30/143 Speed control B60W30/16 takes precedence
• CPC Class Codes: B60W 40/06 Road conditions
• CPC Class Codes: B60W 50/0097 Predicting future conditions
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A method for determining speed set-point values v_ref for a vehicle'"'"'s control systems including determining a horizon from position data and map data of an itinerary made up of route segments with at least one characteristic for each segment; calculating threshold values for the characteristic of segments according to one or more vehicle-specific values, which threshold values serve as boundaries for assigning segments to various categories; comparing the characteristic of each segment with the calculated threshold values and placing each segment within the horizon in a category calculating set-point values for the vehicle'"'"'s control systems across the horizon according to rules pertaining to the categories. When any characteristic in segments within the horizon indicates a hindrance, calculating the vehicle'"'"'s retardation determining a start position within the horizon for commencement of retardation according to its calculated retardation in order to achieve a lowering of the set-point speed v_ref to a maximum speed required by the hindrance at the location of the hindrance; adapting the speed set-point values v_ref within the horizon according to the start position and retardation of the vehicle and regulating the vehicle'"'"'s speed according to the speed set-values v_ref. Also a module determines set-point values for a control system in the vehicle.

Claims

1. A method for determining speed set-point values for a vehicle'"'"'s control systems, the method comprises:

A) determining a horizon using position data and map data of an itinerary made up of route segments with at least one characteristic for each segment;

B) calculating threshold values for said at least one characteristic of segments according to one or more vehicle-specific values, wherein the threshold values serve as boundaries for assigning segments to various categories;

C) comparing said at least one characteristic of each segment with the calculated threshold values and placing each segment within the horizon in a category according to the results of the comparisons;

D) calculating speed set-point values v_ref for the vehicle'"'"'s control systems across the horizon according to rules pertaining to the categories in which segments within the horizon are placed; and

when any characteristic in segments within the horizon indicates a hindrance, performing the following steps;

E) calculating the vehicle'"'"'s retardation on the supposition that the brakes are not used according to said rules pertaining to the segment categories;

F) determining a start position within the horizon for commencement of retardation of the vehicle according to its calculated retardation in order to achieve a lowering of the set-point speed v_ref to a maximum speed required by the hindrance at the location of the hindrance;

G) adapting the speed set-point values v_ref within the horizon according to said start position and retardation of the vehicle;

H) regulating the vehicle'"'"'s speed according to the speed set-values v_ref.

2. A method according to claim 1, wherein the vehicle-specific values are determined by current transmission ratio, current vehicle weight, the engine'"'"'s maximum torque curve, mechanical friction and/or the vehicle'"'"'s running resistance at current speed.

3. A method according to claim 1, wherein a characteristic indicates a hindrance in the form of a speed limit, a sharp bend, a roundabout or an intersection.

4. A method according to claim 3, wherein the maximum speed required by the hindrance limits the vehicle'"'"'s speed for a predetermined length of the horizon.

5. A method according to claim 3, wherein the characteristic indicates a hindrance due to temperature.

6. A method according to claim 3, wherein regulation of the vehicle'"'"'s speed to cater for hindrances is an optional setting for the driver.

7. A method according to claim 1, further comprising after step F) a step F₁) to indicate for the vehicle'"'"'s driver that a speed change is coming, whereupon step G) is performed if the driver so indicates.

8. A method according to claim 1, wherein the itinerary is determined by means of a navigation system.

17. A computer program product comprising computer program instructions for enabling a computer system in a vehicle to perform the steps according to the method according to claim 1 when the computer program instructions are run on said computer system.

18. A computer program product according to claim 17, in which the computer program instructions are stored on a medium which is readable by a computer system.

9. A module for determination of speed set-values v_ref for a vehicle'"'"'s control systems, the module comprising:

a horizon unit configured and operable to determining a horizon using position data and map data of an itinerary made up of segments with at least one characteristic for each segment;

a processor unit configured and operable to;

calculating threshold values for said at least one characteristic of segments according to one or more vehicle-specific values, which threshold values serve as boundaries for assigning segments to various categories;

comparing said at least one characteristic of each segment with the calculated threshold values and placing each segment in a category according to the results of the comparisons;

calculating speed set-point values v_ref for the vehicle'"'"'s control systems across the horizon according to rules pertaining to the categories in which segments within the horizon are placed;

a hindrance unit configured and operable to performing the following steps when any characteristic in segments within the horizon indicates a hindrance;

calculating the vehicle'"'"'s retardation on the supposition that the brakes are not used according to said rules pertaining to the segment categories;

determining a start position within the horizon for commencement of retardation of the vehicle according to its calculated retardation in order to achieve a lowering of the set-point speed v_ref to a maximum speed required by the hindrance at the location of the hindrance; and

the processor unit is further configured and operable to adapting the speed set-values v_ref within the horizon according to said start position and retardation of the vehicle; and

the control system regulates the vehicle'"'"'s speed according to the speed set-values v_ref.

10. A module according to claim 9, in which vehicle-specific values of current transmission ratio, current vehicle weight, the engine'"'"'s maximum torque curve, mechanical friction and/or the vehicle'"'"'s running resistance at current speed are determined.

11. A module according to claim 9, wherein the hindrance unit is configured and operable to detecting a hindrance within the horizon from the fact that a characteristic for a route segment indicates a speed limit, a sharp bend, a roundabout or an intersection etc.

12. A module according to claim 11, wherein the hindrance unit is configured and operable to determining a length of the horizon for which the maximum speed required by the hindrance limits the vehicle'"'"'s speed.

13. A module according to claim 11, wherein the hindrance unit is configured and operable to determining whether the characteristic indicates a hindrance due to some other parameter.

14. A module according to claim 9, wherein the control system being operable for regulating the vehicle'"'"'s speed to cater for hindrances comprises the control system being configured and operable to being an optional setting for the driver.

15. A module according to claim 9, wherein the hindrance unit is configured and operable to indicating for the vehicle'"'"'s driver that a speed change is coming, and to receiving input data which accept or reject the speed change.

16. A module according to claim 9, wherein the horizon unit is configured and operable to determining a horizon of an itinerary which is determined by means of a navigation system.